129 Evaluation of Cotton Gin Byproduct and Whole Cottonseed in Diets for Growing Beef Steers

Abstract Cotton byproducts, such as whole cottonseed (WCS) and cotton gin byproduct (CGB) can be utilized as cattle feed. Our objective was to evaluate the feeding value of WCS and CGB when included in a growing ration. Fifty-six yearling steers with a starting body weight of 288±3.8 kg were used in an 84-day trial. Steers were blocked by weight for pen assignments, and treatments were randomly assigned within pen. The nutritionally balanced diets were fed to appetite as total mixed rations through Calan gates. Treatment 1 (TRT 1), was composed of corn silage, ground corn, and soybean meal. Treatment 2 (TRT 2) replaced some of the corn and soybean meal with WCS (15% of the diet DM). Treatment 3 (TRT 3) replaced some of the silage with CGB (25% of the diet DM). Treatment 4 (TRT 4) replaced some of the corn and soybean meal with WCS (15% of the diet DM) and some of the silage with CGB (25% of the diet DM). Dry matter intake (DMI) was similar for TRT 1 and 2, which were lower (P >0.5) compared to TRT 3 and 4 (8.8, 8.5, 11.3, and 10.3±0.24 kg/d for TRT 1, 2, 3, and 4, respectively). Average daily gain did not differ between TRT 1, 2, and 4, but was higher (P >0.5) for TRT 3 (1.27, 1.18, 1.32, and 1.54 ± 0.05 kg/d for TRT 1, 2, 3, and 4, respectively). Gain to feed ratios were highest (P >0.5) for TRT 1 and 2 compared with TRT 3 and 4 (0.16, 0.15, 0.12, and 0.13±0.009, respectively). This study demonstrates that cotton byproducts can be utilized in growing cattle diets to replace a portion of corn, soybean meal, and corn silage while resulting in similar or enhanced performance.